This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the...This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of view.Then the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system.展开更多
The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precisio...The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precision.To ensure its accuracy of detection,it is necessary to correlate their thermal models to in-orbit da⁃ta.In this work,an investigation of intelligent correlation method named Intelligent Correlation Platform for Ther⁃mal Model(ICP-TM)was established,the advanced Kriging surrogate model and efficient adaptive region opti⁃mization algorithm were introduced.After the correlation with this method for FY-3E/HIRAS-Ⅱ,the results indi⁃cate that compared with the data in orbit,the error of the thermal model has decreased from 5 K to within±1 K in cold case(10℃).Then,the correlated model is validated in hot case(20℃),and the correlated model exhibits good universality.This correlation precision is also much superiors to the general ones like 3 K in other similar lit⁃erature.Furthermore,the process is finished in 8 days using ICP-TM,the efficiency is much better than 3 months based on manual.The results show that the proposed approach significantly enhances the accuracy and efficiency of thermal model,this contributes to the precise thermal control of subsequent infrared optical payloads.展开更多
Real-time polarization medium-wave infrared(MIR)optical imaging systems enable the acquisition of infrared and polarization information for a target.At present,real-time polarization MIR devices face the following pro...Real-time polarization medium-wave infrared(MIR)optical imaging systems enable the acquisition of infrared and polarization information for a target.At present,real-time polarization MIR devices face the following problems:poor real-time performance,low transmission and high requirements for fabrication and integration.Herein,we aim to improve the performance of real-time polarization imaging systems in the MIR waveband and solve the above-mentioned defects.Therefore,we propose a MIR polarization imaging system to achieve real-time polarization-modulated imaging with high transmission as well as improved performance based on a pixel-wise metasurface micro-polarization array(PMMPA).The PMMPA element comprises several linear polarization(LP)filters with different polarization angles.The optimization results demonstrate that the transmittance of the center field of view for the LP filters is up to 77%at a wavelength of4.0μm and an extinction ratio of 88 d B.In addition,a near-diffraction-limited real-time MIR imaging optical system is designed with a field of view of 5°and an F-number of 2.The simulation results show that an MIR polarization imaging system with excellent real-time performance and high transmission is achieved by using the optimized PMMPA element.Therefore,the method is compatible with the available optical system design technologies and provides a way to realize real-time polarization imaging in MIR wavebands.展开更多
We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho：GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.0...We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho：GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.05 W, corresponding to a slope efficiency of 74.6%. The ZGP-OPO laser produces 4.2 ns mid-infrared pulses at a pulse repetition rate of 5 kHz. In addition, we obtain 0.8 um of tunable range for the signal wave and 2.1 um of tunable range for the idler wave.展开更多
We present prism spectro/photo/polarimeters employing linear detector arrays, and their scientific results for this decade. We put emphasis on the educational merits for begginers aiming at astronomical instrumentatio...We present prism spectro/photo/polarimeters employing linear detector arrays, and their scientific results for this decade. We put emphasis on the educational merits for begginers aiming at astronomical instrumentation as well as professional astronomical works.展开更多
China’s ambition to build a 12 m aperture optical/infrared telescope in Tibet has been recently challenged by intense disputes over its design options.The Large Optical/Infrared Telescope,or LOT,which will become the...China’s ambition to build a 12 m aperture optical/infrared telescope in Tibet has been recently challenged by intense disputes over its design options.The Large Optical/Infrared Telescope,or LOT,which will become the world’s biggest upon completion before the 30 m-level ones are in place,is expected to give Chinese astronomers a head start in exploring the early universe and exoplanets among other scientific goals.However,optical engineers and scientists are holding on to very different opinions as for what is the best technical route to get there.展开更多
Erosion test of some infrared （IR） optical crystals （Ge, ZnS, MgF2, and quartz） was conducted with a number of different erodents （glass bead, and angular SiC, SiO2, Al2O3） by a homemade gas-blasting erosion tes...Erosion test of some infrared （IR） optical crystals （Ge, ZnS, MgF2, and quartz） was conducted with a number of different erodents （glass bead, and angular SiC, SiO2, Al2O3） by a homemade gas-blasting erosion tester. The influence of impact angle, impact velocity, erodent, and erosion time on the erosion rate and the effect of erosion on their IR transmittance were studied. The dam- aged surface morphology was characterized by scanning electron microscopy, and the erosion mechanism was explored. All of the materials show the maximum in wear versus impact angle at 90°, confirming their brittle failure behavior. It is found that the erosion rate is dependent on the erodent velocity by a power law, and it is highly correlated to the hardness of the erodent. The erosion rate-time curves do not show an incubation state, but an accelerated erosion period followed a maximum erosion （steady state）. The decrease of IR transmittance is direct proportion to the erosion rate. Although the material loss occurs primarily by brittle process, ductile behavior is clearly an important feature, especially for MgF2 and ZnS.展开更多
It is challenging to cooperatively improve the nonlinear optical(NLO)efficiency and the laser-induced damage threshold(LIDT).This work reports a novel IR NLO materials CsInP_(2)S_(7)(CIPS)designed by combination the s...It is challenging to cooperatively improve the nonlinear optical(NLO)efficiency and the laser-induced damage threshold(LIDT).This work reports a novel IR NLO materials CsInP_(2)S_(7)(CIPS)designed by combination the strategies of alkali metals substitution and microscopic NLO units PS4 introduction based on AgGaS_(2).CIPS was composed of strongly distorted[InS_(6)]^(9-)octahedra and[P_(2)S_(7)]4-dimers constructed by corner-sharing[PS_(4)]^(3-),which increase the NLO efficiency and decrease thermal expansion anisotropy simultaneously.Compared with AgGaS_(2),CIPS exhibited strong phase matchable NLO response ca.1.1×AGS@2.1μm,high LIDT ca.20.8×AgGaS_(2),and IR transparency up to 15.3μm.Structural analysis and theoretical investigation confirmed that large SHG effect and ultrahigh LIDT of CIPS originated from the synergistic contribution of[InS_(6)]^(9-)octahedra and[P_(2)S_(7)]4-dimers.These results indicate that CIPS is a promising NLO candidate in the mid-IR region,and this study provides a new approach for developing potential NLO-LIDT compatible materials.展开更多
Crystal structure regulation and optical performance enhancement are huge challenges,especially for the laborious and inefficient trial-and-error method,in the research on infrared nonlinear optical(IR NLO)materials.I...Crystal structure regulation and optical performance enhancement are huge challenges,especially for the laborious and inefficient trial-and-error method,in the research on infrared nonlinear optical(IR NLO)materials.In this work,multi-step cation substitutions were adopted to modulate the crystal structure for the effective design of well-performing IR NLO materials.Specifically,starting from the famous AgGaS_(2)(AGS,I42d)crystal,Ag_(2)CdSiS_(4)(Pmn2_(1))with diamond-like crystal structure,BaAg_(2)SiS_(4)(I42m)with threedimensional tunnel structure and LaAgSiS_(4)(Ama2)with two-dimensional layer structure were designed and experimentally synthesized through multi-step cation substitutions.Structural analysis reveals the fundamental reason of their tetrahedral framework transformation:the size effect of cations and the reduction of component tetrahedra caused by cationic substitution change the assembly mode of the tetrahedral units.Additionally,three non-centrosymmetric Ag-based thiosilicates exhibit wide transmittance range(0.5-17μm),higher laser-induced damage thresholds(2 times that of AGS)and significant phase-matchable second harmonic generation(SHG)enhancement from 0.6 to 3.2 times that of AGS.This work demonstrates that multi-step cation substitution is an effective way to extend non-centrosymmetric structures,which facilitate the exploration of potential infrared nonlinear optical materials.展开更多
Infrared(IR)nonlinear optical(NLO)materials with simultaneous strong NLO coefficient and high laserinduced damaged threshold(LIDT)are the urgently desired optical performance NLO materials in laser application.Here,tw...Infrared(IR)nonlinear optical(NLO)materials with simultaneous strong NLO coefficient and high laserinduced damaged threshold(LIDT)are the urgently desired optical performance NLO materials in laser application.Here,two different electropositive alkali elements are concurrently incorporated into a tetrahedral GaS_(4) anionic framework,affording the first polar quaternary sulphide CsLiGa_(6)S_(10)(CLGS)with mixed ordered alkali cations through the solid-state method.CLGS displays a wide band gap(3.25 eV)originating from the GaS_(4) anionic framework and assistant of the‘dimensional reduction’effect by involving two alkali cations.This merit,accompanied by extremely small anisotropy of the thermal expansion of crystal CLGS(0.05)enhances the LIDT(51.0 MW cm^(2))of 4.5 times that of benchmark AgGaS_(2)(11.3 MW cm^(2))at 1064 nm with the pulse width of 10 ns.Phase CLGS adopts a diamond-like anionic framework in which all tetrahedra are arranged in a highly oriented manner,providing a critical contribution to modest second-harmonic generation 0.7 times that of AgGaS_(2) with a phase-matchable behaviour at the 1910 nm laser.These attributes,along with broad transmittance,warrant the further exploration of potential IR NLO chalcogenides containing multiple alkali cations.展开更多
Developing high-performance infrared(IR)nonlinear optical(NLO)materials is essential for modern laser technology,but challenging due to the competition of the NLO coefficient and band gap in the structure.Based on the...Developing high-performance infrared(IR)nonlinear optical(NLO)materials is essential for modern laser technology,but challenging due to the competition of the NLO coefficient and band gap in the structure.Based on the“electronic structure engineering bucket effect”and systematic experimental investigations on the A^(Ⅱ)B^(Ⅱ)C^(Ⅳ)D_(4)^(Ⅵ)family,three new alkaline earth metal sulfides Mg_(0.6)Cd_(1.4)GeS_(4),CaCdGeS_(4),and BaZnGeS_(4)have been developed.The compounds show a structural change from the Pnma(CaCdGeS_(4))to the Fdd2(BaZnGeS_(4))space group.Among them,BaZnGeS_(4)exhibits a phase-matching NLO response of~0.8×AGS,a wide band gap of 3.36 eV,and a high laser-induced damage threshold of~5.4×AGS,achieving a good balance between the NLO response and band gap,which makes it an excellent IR NLO material.Theoretical calculations show that the NLO effects of BaZnGeS_(4)originated from the[ZnS_(4)]and[GeS_(4)]NLO-active motifs.The results indicate that BaZnGeS_(4)is a promising anti-laser damage IR NLO material and enriches the chemical diversity of the A^(Ⅱ)B^(Ⅱ)C^(Ⅳ)D_(4)^(Ⅵ)family.展开更多
The development of Eu-based chalcogenides with exceptional nonlinear optical(NLO)performance in the infrared(IR)region has garnered increasing attention.However,the design and synthesis of such compounds with non-cent...The development of Eu-based chalcogenides with exceptional nonlinear optical(NLO)performance in the infrared(IR)region has garnered increasing attention.However,the design and synthesis of such compounds with non-centrosymmetric(NCS)structures remain a significant challenge.In this study,we report the successful synthesis of a novel quaternary Eu-based chalcogenide,β-EuZnGeS_(4),achieved through an isovalent cation substitution strategy starting from the ternary parent compound Eu_(2)GeS_(4).This innovative approach induces a structural transformation from centrosymmetric to non-centrosymmetric,thereby enhancing the NLO properties.β-EuZnGeS_(4)crystallizes in the orthorhombic Fdd2 space group,with a unique two-dimensional[ZnGeS_(4)]^(2−) layer structure that accommodates Eu^(2+)cations.Notably,β-EuZnGeS_(4) exhibits a well-balanced set of optical properties,including a remarkable phasematching second-harmonic generation(SHG)effect,with its maximum SHG value being twice that of AgGaS_(2) with a 2050 nm laser.Additionally,it exhibits a high laser-induced damage threshold,surpassing AgGaS_(2) by a factor of 13.1,along with a broad transparency window extending from 0.39 to 23.7μm.Theoretical calculations further reveal that these outstanding optical properties stem from the synergistic effects of the highly distorted tetrahedral[ZnS_(4)]and[GeS_(4)]motifs within the crystal lattice.This work not only expands the materials database for rare-earth metal chalcogenides but also provides a novel strategy for designing NCS structures with tailored optical properties for a wide range of applications.展开更多
Among infrared(IR)nonlinear optical(NLO)materials,metal chalcohalides have become prominent because of their well-balanced performance and are widely applied in optoelectronics,communications,and sensor technology.Str...Among infrared(IR)nonlinear optical(NLO)materials,metal chalcohalides have become prominent because of their well-balanced performance and are widely applied in optoelectronics,communications,and sensor technology.Structural-template-oriented synthesis is an important method in the exploration of metal chalcohalides,mainly focusing on anion/cation substitution,co-substitution and structure prediction.展开更多
The performance of infrared(IR)nonlinear optical(NLO)materials is significantly affected by the thermal conductivity kL,but studies on the structure and property relationship of kL in these materials are very rare.In ...The performance of infrared(IR)nonlinear optical(NLO)materials is significantly affected by the thermal conductivity kL,but studies on the structure and property relationship of kL in these materials are very rare.In this work we evaluated the k_(L) in IR NLO multicomponent chalcogenides Li_(x)Ag_(1-x)Ga_(y)In_(1-y)Se_(2) with a smooth change in the compositions x and y by using a machine learning approach and laser flash measurements,combined with available experimental results.The found patterns of kL dependence on the atomic mass,bond length and electronegativity provide an effective understanding for navigation in the process of searching for new chalcogenide crystals with an optimal set of parameters that allow them to be effectively used as a frequency converter of laser radiation in the IR range.Moreover,the compositions Li_(0.5)Ag_(0.5)GaSe_(2),Li_(0.81)Ag_(0.19)InSe_(2) and AgGa_(0.5)In_(0.5)Se_(2) are demonstrated to exhibit a balanced combination of the parameters kL,NLOeffects,energy band gaps,and birefringence for IR NLO applications.展开更多
Exploration of new material systems and optical performance enhancement are huge challenges for the study of infrared nonlinear optical(IR NLO)materials.In this work,the first thioborate-thiogermanate and thioborate-t...Exploration of new material systems and optical performance enhancement are huge challenges for the study of infrared nonlinear optical(IR NLO)materials.In this work,the first thioborate-thiogermanate and thioborate-thiostannate compounds,Ca_(2)La(Ge_(0.72)Si_(0.28)S_(4))(BS_(3))and Ca_(2)La(Sn_(0.75)Si_(0.25)S_(4))(BS_(3)),containing both co-occupied Ca^(2+)/La^(3+)cation and[Ge/SiS_(4)]^(4-)or[Sn/SiS_(4)]^(4-)anion sites,respectively,were designed through an atomic site co-occupancy strategy.They inherited favourable 3D network structures in which the effectively aligned[MS_(4)]^(4-)and[BS_(3)]^(3-)functional anions were bridged by Ca^(2+)/La^(3+)cations.Remarkably,the title compounds achieved excellent IR NLO properties,including good chemical and thermal stabilities,wide light transmission ranges(0.45-11μm),strong second harmonic generation responses(1.5 and 2.0 times that of commercial AgGaS2 at 2.05μm)and high laser-induced damage thresholds(7 and 6 times that of AgGaS2).Theoretical calculation and experimental results revealed that,on the basis of excellent structural framework,introducing more active functional groups through atomic site co-occupancy could simultaneously enhance the second harmonic generation effect and maintain a relatively high laser-induced damage threshold.This work not only offers an easier synthetic route for mixed anionic thioborates but also provides inspiration for the design of well-performed NLO materials.展开更多
Infrared nonlinear optical(NLO)materials are crucial to the development of laser technology.However,finding ways to effectively synthesize them is still a big challenge.Herein,aided by a stable open framework,four IR ...Infrared nonlinear optical(NLO)materials are crucial to the development of laser technology.However,finding ways to effectively synthesize them is still a big challenge.Herein,aided by a stable open framework,four IR NLO materials,MMn_(6)Ga_(6)S_(16)(M=Ca,Sr,Ba,and Pb),have been effectively synthesized in a high-temperature vacuum sealing system.They all crystallize in a non-centrosymmetric(NCS)space group,P6¯,and their structures feature a three-dimensional open framework composed of Mn-S single and double chains and Ga-S single and double chains,in which these one-dimensional chains increase the structural flexibility and adjustability to accommodate varied cations with different ionic radii.Remarkably,MMn_(6)Ga_(6)S_(16)(M=Ca,Sr,Ba,and Pb)exhibit not only comprehensive NLO performances including appropriate NLO responses and band gaps and a wide transmission range but also para-magnetism in magnetic properties,indicating that MMn_(6)Ga_(6)S_(16)(M=Ca,Sr,Ba,and Pb)are potential IR multifunctional materials.This work suggests that a stable open framework can be used to construct varied structures,which brings a new platform for effectively designing multifunctional materials.展开更多
Infrared nonlinear optical(IR-NLO)materials play a vital role in generating IR laser output and have significant applications in the fields of communication,medicine,and security.At present,commercial IR-NLO crystals ...Infrared nonlinear optical(IR-NLO)materials play a vital role in generating IR laser output and have significant applications in the fields of communication,medicine,and security.At present,commercial IR-NLO crystals suffer from various performance drawbacks that constrain their range of applications.Therefore,the pursuit of designing and exploring new IR-NLO materials has emerged as an important avenue for the advancement of the IR laser industry.Benefiting from the various structural compositions,wide energy gaps,sufficient second-harmonic-generation intensities,strong laser-induced damage thresholds and favorable phase matching features,Mg-based IR-NLO materials have attracted wide attention in recent years.However,there has not been a specific review of this attractive family.展开更多
Thioantimonates containing high oxidation state Sb^(5+)have been proven to exhibit excellent performance in the design of new materials such as infrared optical crystals and lithium-ion batteries.However,as described ...Thioantimonates containing high oxidation state Sb^(5+)have been proven to exhibit excellent performance in the design of new materials such as infrared optical crystals and lithium-ion batteries.However,as described by the“inert pair effect”,the preparation of P-block elements containing high oxidation states in sealed systems has been a challenge.In this study,an aliovalent cation substitution strategy was used to design and synthesize three novel thioantimonates(V),A_(4)BaSb_(2)Se_(8)(A=Cs,Rb)and Rb_(2)BaSbS_(4)Cl(RBSSC),respectively,all of which contain rare[SbS_(4)]tetrahedral units.The introduction of Ba^(2+)ions leads to the distortion and high-density arrangement of[SbSe_(4)]units,which is manifested as a significant 3.7 times enhancement of the birefringence compared to that of the parent compound Cs_(3)SbSe_(4)(0.041→Cs_(4)BaSb_(2)Se_(8)0.150@1064 nm).By further introducing highly electronegative halogen atoms,the first antimony-based thiohalide(V)RBSSC was synthesized.Theoretical calculations show that the band gap of RBSSC is up to 3.674 eV,larger than those of all known antimony-based thiohalides(III).This work provides strong evidence that the aliovalent cation substitution strategy is an effective way to find new thioantimonate(V)families,and also indicates that the cation size effect introduced by elemental substitution may lead to surprising performance improvements.展开更多
Infrared(IR)nonlinear optical(NLO)materials have attracted tremendous interest for civil and military applications,but it remains a great contemporary challenge to develop high-effciency NLO crystals that possess suff...Infrared(IR)nonlinear optical(NLO)materials have attracted tremendous interest for civil and military applications,but it remains a great contemporary challenge to develop high-effciency NLO crystals that possess suffciently high second-harmonic generation(SHG)effciencies coupled to wide transparency ranges and high laser damage thresholds.A series of new hydrous rare-earth iodates RE(IO_(3))_(3)·(H_(2)O)(RE=Y 1,Eu 2)and La_(2)(IO_(3))_(6)(H_(2)O)(3)have been synthesized through facile hydrothermal methods.1 and 2 are isostructural,crystallizing in the polar space group P21,while 3 crystallizes in the polar space group Pc.1-3 feature three-dimensional(3D)frameworks composed of alternately connected corner-shared dis torted[REO_(x)]polyhedra(RE=Y,Eu,and La;x=8,9)and[IO_(3)]^(−)groups.Optical studies showed that 1–3 exhibit good NLO properties,including strong SHG intensities(3.0×(1),4.5×(2),and 1.5×KH_(2)PO_(4)(3)),large band gaps(4.12(1),4.36(2),and 4.24 eV(3),with 2 possessing the largest band gap among the known SHG-active rare-earth-based iodates,high laser damage thresholds(LDT)(53×(1),43×(2),and 44×AgGaS_(2)(3)),and wide transparency ranges(ca.3.0–11.3μm)in the mid-IR region covering two criti cal IR transparency windows;1–3 are therefore potential candidate NLO materials.Density functional theory calculations on 1–3 confirm that their strong SHG responses and large band gaps are mainly derived from the synergistic effect of[IO_(3)]^(−)groups and rare-earth oxide polyhedra[REOx]in their 3D frameworks.We conclude that the introduction of rare-earth cations with moderate electropositivity into iodates may optimize the balance between SHG effciency and optical band gaps,the key requirement for high-performance NLO materials for practical applications.展开更多
The search for new non-centrosymmetric(NCS)crystals with wide energy-gaps(Eg)and strong secondharmonic generation(SHG)responses has become one of the greatest challenges in the mid-and farinfrared(MFIR)nonlinear optic...The search for new non-centrosymmetric(NCS)crystals with wide energy-gaps(Eg)and strong secondharmonic generation(SHG)responses has become one of the greatest challenges in the mid-and farinfrared(MFIR)nonlinear optical(NLO)field.In this work,a novel quaternary NCS material Sr_(5)ZnGa_(6)S_(15)(SZGS),which contains a complex 3D anionic framework and possesses the optical properties required for the MFIR NLO applications,especially the good balance between wide Eg(3.15 eV)and large SHG response(d_(ij)=1.2×AgGaS_(2)),has been discovered for the first time.Moreover,the result of theoretical calculation further indicates that the 3D[ZnGa_(6)S_(15)]^(10−)framework makes definitive contributions to the NLO properties.All these studies demonstrate that SZGS is a promising NLO candidate in the MFIR region.展开更多
基金Sponsored by the National High Technology Research and Development Program of China(Grant No.863-2-5-1-13B)
文摘This article describes a novel configuration design for a re-imaging off-axis catadioptric space infrared optical system,and in order to satisfy the signal noise ratio requirements of the system,the stray light of the system is necessary to analyze and restrain. The optical system with a focal length of 1 200 mm,an entrance pupil diameter of 600 mm,an F-number of 2,a field of view of 3°× 0. 15°,a working wave band of 8 μm-10 μm,and the image quality of the optical system almost approach to diffraction limits in all field of view.Then the mathematical models of stray light are built,and the suppressive structure is established to eliminate the effect of stray light. Finally,TraceP ro is used to analyze and simulate stray light with and without the suppressive structure,and also get the results of the PST curves. The results indicate that appropriate optical system and suppressive structure can highly reduce the stray light of the space infrared optical system.
基金Supported by the National Key Research and Development Program of China(2022YFB3904803)。
文摘The Infrared Hyperspectral Atmospheric SounderⅡ(HIRAS-Ⅱ)is the key equipment on FengYun-3E(FY-3E)satellite,which can realize vertical atmospheric detection,featuring hyper spectral,high sensitivity and high precision.To ensure its accuracy of detection,it is necessary to correlate their thermal models to in-orbit da⁃ta.In this work,an investigation of intelligent correlation method named Intelligent Correlation Platform for Ther⁃mal Model(ICP-TM)was established,the advanced Kriging surrogate model and efficient adaptive region opti⁃mization algorithm were introduced.After the correlation with this method for FY-3E/HIRAS-Ⅱ,the results indi⁃cate that compared with the data in orbit,the error of the thermal model has decreased from 5 K to within±1 K in cold case(10℃).Then,the correlated model is validated in hot case(20℃),and the correlated model exhibits good universality.This correlation precision is also much superiors to the general ones like 3 K in other similar lit⁃erature.Furthermore,the process is finished in 8 days using ICP-TM,the efficiency is much better than 3 months based on manual.The results show that the proposed approach significantly enhances the accuracy and efficiency of thermal model,this contributes to the precise thermal control of subsequent infrared optical payloads.
基金Project supported by the National Key R&D Program of China(Grant No.SKLA02020001A05)。
文摘Real-time polarization medium-wave infrared(MIR)optical imaging systems enable the acquisition of infrared and polarization information for a target.At present,real-time polarization MIR devices face the following problems:poor real-time performance,low transmission and high requirements for fabrication and integration.Herein,we aim to improve the performance of real-time polarization imaging systems in the MIR waveband and solve the above-mentioned defects.Therefore,we propose a MIR polarization imaging system to achieve real-time polarization-modulated imaging with high transmission as well as improved performance based on a pixel-wise metasurface micro-polarization array(PMMPA).The PMMPA element comprises several linear polarization(LP)filters with different polarization angles.The optimization results demonstrate that the transmittance of the center field of view for the LP filters is up to 77%at a wavelength of4.0μm and an extinction ratio of 88 d B.In addition,a near-diffraction-limited real-time MIR imaging optical system is designed with a field of view of 5°and an F-number of 2.The simulation results show that an MIR polarization imaging system with excellent real-time performance and high transmission is achieved by using the optimized PMMPA element.Therefore,the method is compatible with the available optical system design technologies and provides a way to realize real-time polarization imaging in MIR wavebands.
基金Supported by the National Natural Science Foundation of China under Grant No 51572053
文摘We demonstrate a middle infrared ZnGeP_2 optical parametric oscillator pumped by the Q-switched Ho：GdVO_4 laser. When the incident Ho pump power is 4.12 W, the maximum average output power of the ZGP-OPO laser is 2.05 W, corresponding to a slope efficiency of 74.6%. The ZGP-OPO laser produces 4.2 ns mid-infrared pulses at a pulse repetition rate of 5 kHz. In addition, we obtain 0.8 um of tunable range for the signal wave and 2.1 um of tunable range for the idler wave.
文摘We present prism spectro/photo/polarimeters employing linear detector arrays, and their scientific results for this decade. We put emphasis on the educational merits for begginers aiming at astronomical instrumentation as well as professional astronomical works.
文摘China’s ambition to build a 12 m aperture optical/infrared telescope in Tibet has been recently challenged by intense disputes over its design options.The Large Optical/Infrared Telescope,or LOT,which will become the world’s biggest upon completion before the 30 m-level ones are in place,is expected to give Chinese astronomers a head start in exploring the early universe and exoplanets among other scientific goals.However,optical engineers and scientists are holding on to very different opinions as for what is the best technical route to get there.
基金supported by the National Natural Science Foundation of China (No.50572007)
文摘Erosion test of some infrared （IR） optical crystals （Ge, ZnS, MgF2, and quartz） was conducted with a number of different erodents （glass bead, and angular SiC, SiO2, Al2O3） by a homemade gas-blasting erosion tester. The influence of impact angle, impact velocity, erodent, and erosion time on the erosion rate and the effect of erosion on their IR transmittance were studied. The dam- aged surface morphology was characterized by scanning electron microscopy, and the erosion mechanism was explored. All of the materials show the maximum in wear versus impact angle at 90°, confirming their brittle failure behavior. It is found that the erosion rate is dependent on the erodent velocity by a power law, and it is highly correlated to the hardness of the erodent. The erosion rate-time curves do not show an incubation state, but an accelerated erosion period followed a maximum erosion （steady state）. The decrease of IR transmittance is direct proportion to the erosion rate. Although the material loss occurs primarily by brittle process, ductile behavior is clearly an important feature, especially for MgF2 and ZnS.
基金the Natural Science Foundation of China(No.22105218).
文摘It is challenging to cooperatively improve the nonlinear optical(NLO)efficiency and the laser-induced damage threshold(LIDT).This work reports a novel IR NLO materials CsInP_(2)S_(7)(CIPS)designed by combination the strategies of alkali metals substitution and microscopic NLO units PS4 introduction based on AgGaS_(2).CIPS was composed of strongly distorted[InS_(6)]^(9-)octahedra and[P_(2)S_(7)]4-dimers constructed by corner-sharing[PS_(4)]^(3-),which increase the NLO efficiency and decrease thermal expansion anisotropy simultaneously.Compared with AgGaS_(2),CIPS exhibited strong phase matchable NLO response ca.1.1×AGS@2.1μm,high LIDT ca.20.8×AgGaS_(2),and IR transparency up to 15.3μm.Structural analysis and theoretical investigation confirmed that large SHG effect and ultrahigh LIDT of CIPS originated from the synergistic contribution of[InS_(6)]^(9-)octahedra and[P_(2)S_(7)]4-dimers.These results indicate that CIPS is a promising NLO candidate in the mid-IR region,and this study provides a new approach for developing potential NLO-LIDT compatible materials.
基金supported by the National Natural Science Foundation of China(No.22031009,22375201 and 21921001).
文摘Crystal structure regulation and optical performance enhancement are huge challenges,especially for the laborious and inefficient trial-and-error method,in the research on infrared nonlinear optical(IR NLO)materials.In this work,multi-step cation substitutions were adopted to modulate the crystal structure for the effective design of well-performing IR NLO materials.Specifically,starting from the famous AgGaS_(2)(AGS,I42d)crystal,Ag_(2)CdSiS_(4)(Pmn2_(1))with diamond-like crystal structure,BaAg_(2)SiS_(4)(I42m)with threedimensional tunnel structure and LaAgSiS_(4)(Ama2)with two-dimensional layer structure were designed and experimentally synthesized through multi-step cation substitutions.Structural analysis reveals the fundamental reason of their tetrahedral framework transformation:the size effect of cations and the reduction of component tetrahedra caused by cationic substitution change the assembly mode of the tetrahedral units.Additionally,three non-centrosymmetric Ag-based thiosilicates exhibit wide transmittance range(0.5-17μm),higher laser-induced damage thresholds(2 times that of AGS)and significant phase-matchable second harmonic generation(SHG)enhancement from 0.6 to 3.2 times that of AGS.This work demonstrates that multi-step cation substitution is an effective way to extend non-centrosymmetric structures,which facilitate the exploration of potential infrared nonlinear optical materials.
基金supported by the National Natural Science Foundation of China(21921001,21827813,92161125,22075283,and 22175172)the Youth Innovation Promotion Association of Chinese Academy of Sciences(2021300)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2020ZZ108,2021ZR205).
文摘Infrared(IR)nonlinear optical(NLO)materials with simultaneous strong NLO coefficient and high laserinduced damaged threshold(LIDT)are the urgently desired optical performance NLO materials in laser application.Here,two different electropositive alkali elements are concurrently incorporated into a tetrahedral GaS_(4) anionic framework,affording the first polar quaternary sulphide CsLiGa_(6)S_(10)(CLGS)with mixed ordered alkali cations through the solid-state method.CLGS displays a wide band gap(3.25 eV)originating from the GaS_(4) anionic framework and assistant of the‘dimensional reduction’effect by involving two alkali cations.This merit,accompanied by extremely small anisotropy of the thermal expansion of crystal CLGS(0.05)enhances the LIDT(51.0 MW cm^(2))of 4.5 times that of benchmark AgGaS_(2)(11.3 MW cm^(2))at 1064 nm with the pulse width of 10 ns.Phase CLGS adopts a diamond-like anionic framework in which all tetrahedra are arranged in a highly oriented manner,providing a critical contribution to modest second-harmonic generation 0.7 times that of AgGaS_(2) with a phase-matchable behaviour at the 1910 nm laser.These attributes,along with broad transmittance,warrant the further exploration of potential IR NLO chalcogenides containing multiple alkali cations.
基金supported by the High-level Talent Project of Xinjiang Uygur Autonomous Region(2020000039)the National Natural Science Foundation of China(52002398,61835014,and 51972336)+1 种基金the West Light Foundation of the CAS(2019-YDYLTD-002)the Xinjiang Key Laboratory of Electronic Information Materials and Devices(2017D04029).
文摘Developing high-performance infrared(IR)nonlinear optical(NLO)materials is essential for modern laser technology,but challenging due to the competition of the NLO coefficient and band gap in the structure.Based on the“electronic structure engineering bucket effect”and systematic experimental investigations on the A^(Ⅱ)B^(Ⅱ)C^(Ⅳ)D_(4)^(Ⅵ)family,three new alkaline earth metal sulfides Mg_(0.6)Cd_(1.4)GeS_(4),CaCdGeS_(4),and BaZnGeS_(4)have been developed.The compounds show a structural change from the Pnma(CaCdGeS_(4))to the Fdd2(BaZnGeS_(4))space group.Among them,BaZnGeS_(4)exhibits a phase-matching NLO response of~0.8×AGS,a wide band gap of 3.36 eV,and a high laser-induced damage threshold of~5.4×AGS,achieving a good balance between the NLO response and band gap,which makes it an excellent IR NLO material.Theoretical calculations show that the NLO effects of BaZnGeS_(4)originated from the[ZnS_(4)]and[GeS_(4)]NLO-active motifs.The results indicate that BaZnGeS_(4)is a promising anti-laser damage IR NLO material and enriches the chemical diversity of the A^(Ⅱ)B^(Ⅱ)C^(Ⅳ)D_(4)^(Ⅵ)family.
基金supported by the National Natural Science Foundation of China(22175175)Natural Science Foundation of Fujian Province(2022L3092 and 2023H0041)+1 种基金Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR118)the Youth Innovation Promotion Association CAS(2022303).
文摘The development of Eu-based chalcogenides with exceptional nonlinear optical(NLO)performance in the infrared(IR)region has garnered increasing attention.However,the design and synthesis of such compounds with non-centrosymmetric(NCS)structures remain a significant challenge.In this study,we report the successful synthesis of a novel quaternary Eu-based chalcogenide,β-EuZnGeS_(4),achieved through an isovalent cation substitution strategy starting from the ternary parent compound Eu_(2)GeS_(4).This innovative approach induces a structural transformation from centrosymmetric to non-centrosymmetric,thereby enhancing the NLO properties.β-EuZnGeS_(4)crystallizes in the orthorhombic Fdd2 space group,with a unique two-dimensional[ZnGeS_(4)]^(2−) layer structure that accommodates Eu^(2+)cations.Notably,β-EuZnGeS_(4) exhibits a well-balanced set of optical properties,including a remarkable phasematching second-harmonic generation(SHG)effect,with its maximum SHG value being twice that of AgGaS_(2) with a 2050 nm laser.Additionally,it exhibits a high laser-induced damage threshold,surpassing AgGaS_(2) by a factor of 13.1,along with a broad transparency window extending from 0.39 to 23.7μm.Theoretical calculations further reveal that these outstanding optical properties stem from the synergistic effects of the highly distorted tetrahedral[ZnS_(4)]and[GeS_(4)]motifs within the crystal lattice.This work not only expands the materials database for rare-earth metal chalcogenides but also provides a novel strategy for designing NCS structures with tailored optical properties for a wide range of applications.
基金supported by the National Natural Science Foundation of China(22205024 and 22193043),the Interdisciplinary Intelligence Supercomputer Center of Beijing Normal University,Zhuhai,and the Instrumentation and Service Center for Science and Technology,Beijing Normal University,Zhuhai.
文摘Among infrared(IR)nonlinear optical(NLO)materials,metal chalcohalides have become prominent because of their well-balanced performance and are widely applied in optoelectronics,communications,and sensor technology.Structural-template-oriented synthesis is an important method in the exploration of metal chalcohalides,mainly focusing on anion/cation substitution,co-substitution and structure prediction.
基金supported by the National Natural Science Foundation of China(Grant No.22133004)the Ministry of Education and Science of the Russian Federation,Grant FSUS-2025-0011(crystal structure analysis)partly by the state assignment of IGM SB RAS No.122041400031-2(crystal growth).
文摘The performance of infrared(IR)nonlinear optical(NLO)materials is significantly affected by the thermal conductivity kL,but studies on the structure and property relationship of kL in these materials are very rare.In this work we evaluated the k_(L) in IR NLO multicomponent chalcogenides Li_(x)Ag_(1-x)Ga_(y)In_(1-y)Se_(2) with a smooth change in the compositions x and y by using a machine learning approach and laser flash measurements,combined with available experimental results.The found patterns of kL dependence on the atomic mass,bond length and electronegativity provide an effective understanding for navigation in the process of searching for new chalcogenide crystals with an optimal set of parameters that allow them to be effectively used as a frequency converter of laser radiation in the IR range.Moreover,the compositions Li_(0.5)Ag_(0.5)GaSe_(2),Li_(0.81)Ag_(0.19)InSe_(2) and AgGa_(0.5)In_(0.5)Se_(2) are demonstrated to exhibit a balanced combination of the parameters kL,NLOeffects,energy band gaps,and birefringence for IR NLO applications.
基金supported by the National Natural Science Foundation of China(No.22031009,22375201,and 21921001)the Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences(CXZX-2022-GH06).
文摘Exploration of new material systems and optical performance enhancement are huge challenges for the study of infrared nonlinear optical(IR NLO)materials.In this work,the first thioborate-thiogermanate and thioborate-thiostannate compounds,Ca_(2)La(Ge_(0.72)Si_(0.28)S_(4))(BS_(3))and Ca_(2)La(Sn_(0.75)Si_(0.25)S_(4))(BS_(3)),containing both co-occupied Ca^(2+)/La^(3+)cation and[Ge/SiS_(4)]^(4-)or[Sn/SiS_(4)]^(4-)anion sites,respectively,were designed through an atomic site co-occupancy strategy.They inherited favourable 3D network structures in which the effectively aligned[MS_(4)]^(4-)and[BS_(3)]^(3-)functional anions were bridged by Ca^(2+)/La^(3+)cations.Remarkably,the title compounds achieved excellent IR NLO properties,including good chemical and thermal stabilities,wide light transmission ranges(0.45-11μm),strong second harmonic generation responses(1.5 and 2.0 times that of commercial AgGaS2 at 2.05μm)and high laser-induced damage thresholds(7 and 6 times that of AgGaS2).Theoretical calculation and experimental results revealed that,on the basis of excellent structural framework,introducing more active functional groups through atomic site co-occupancy could simultaneously enhance the second harmonic generation effect and maintain a relatively high laser-induced damage threshold.This work not only offers an easier synthetic route for mixed anionic thioborates but also provides inspiration for the design of well-performed NLO materials.
基金supported by the National Natural Science Foundation of China(grant no.52322202,52172006 and 22071179)the Natural Science Foundation of Tianjin(grant no.20JCJQJC00060 and 21JCJQJC00090).
文摘Infrared nonlinear optical(NLO)materials are crucial to the development of laser technology.However,finding ways to effectively synthesize them is still a big challenge.Herein,aided by a stable open framework,four IR NLO materials,MMn_(6)Ga_(6)S_(16)(M=Ca,Sr,Ba,and Pb),have been effectively synthesized in a high-temperature vacuum sealing system.They all crystallize in a non-centrosymmetric(NCS)space group,P6¯,and their structures feature a three-dimensional open framework composed of Mn-S single and double chains and Ga-S single and double chains,in which these one-dimensional chains increase the structural flexibility and adjustability to accommodate varied cations with different ionic radii.Remarkably,MMn_(6)Ga_(6)S_(16)(M=Ca,Sr,Ba,and Pb)exhibit not only comprehensive NLO performances including appropriate NLO responses and band gaps and a wide transmission range but also para-magnetism in magnetic properties,indicating that MMn_(6)Ga_(6)S_(16)(M=Ca,Sr,Ba,and Pb)are potential IR multifunctional materials.This work suggests that a stable open framework can be used to construct varied structures,which brings a new platform for effectively designing multifunctional materials.
基金sponsored by the National Natural Science Foundation of China(21771179)Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China(2021ZR118)the Natural Science Foundation of Fujian Province(2022L3092 and 2023H0041).
文摘Infrared nonlinear optical(IR-NLO)materials play a vital role in generating IR laser output and have significant applications in the fields of communication,medicine,and security.At present,commercial IR-NLO crystals suffer from various performance drawbacks that constrain their range of applications.Therefore,the pursuit of designing and exploring new IR-NLO materials has emerged as an important avenue for the advancement of the IR laser industry.Benefiting from the various structural compositions,wide energy gaps,sufficient second-harmonic-generation intensities,strong laser-induced damage thresholds and favorable phase matching features,Mg-based IR-NLO materials have attracted wide attention in recent years.However,there has not been a specific review of this attractive family.
基金supported by the Natural Science Foundation of the Xinjiang Uygur Autonomous Region(2022D01B206 and 2023D01A04)Shanghai Cooperation Organization Science and Technology Partnership Program(2023E01001)+1 种基金the National Natural Science Foundation of China(62305382 and 52302011)support from Tianchi Doctor Plan of Xinjiang Uygur Autonomous Region。
文摘Thioantimonates containing high oxidation state Sb^(5+)have been proven to exhibit excellent performance in the design of new materials such as infrared optical crystals and lithium-ion batteries.However,as described by the“inert pair effect”,the preparation of P-block elements containing high oxidation states in sealed systems has been a challenge.In this study,an aliovalent cation substitution strategy was used to design and synthesize three novel thioantimonates(V),A_(4)BaSb_(2)Se_(8)(A=Cs,Rb)and Rb_(2)BaSbS_(4)Cl(RBSSC),respectively,all of which contain rare[SbS_(4)]tetrahedral units.The introduction of Ba^(2+)ions leads to the distortion and high-density arrangement of[SbSe_(4)]units,which is manifested as a significant 3.7 times enhancement of the birefringence compared to that of the parent compound Cs_(3)SbSe_(4)(0.041→Cs_(4)BaSb_(2)Se_(8)0.150@1064 nm).By further introducing highly electronegative halogen atoms,the first antimony-based thiohalide(V)RBSSC was synthesized.Theoretical calculations show that the band gap of RBSSC is up to 3.674 eV,larger than those of all known antimony-based thiohalides(III).This work provides strong evidence that the aliovalent cation substitution strategy is an effective way to find new thioantimonate(V)families,and also indicates that the cation size effect introduced by elemental substitution may lead to surprising performance improvements.
基金supported by the National Natural Science Foundation of China(no.51432006)the Ministry of Education of China for the Changjiang Innovation Research Team(no.IRT13R24)+1 种基金the Ministry of Education and the State Administration of Foreign Experts Affairs for the 111 Project(no.B13025)the Innovation Program of Shanghai Municipal Education Commission.M.G.H.and C.Z.thank the Australian Research Council for support(DP170100411).
文摘Infrared(IR)nonlinear optical(NLO)materials have attracted tremendous interest for civil and military applications,but it remains a great contemporary challenge to develop high-effciency NLO crystals that possess suffciently high second-harmonic generation(SHG)effciencies coupled to wide transparency ranges and high laser damage thresholds.A series of new hydrous rare-earth iodates RE(IO_(3))_(3)·(H_(2)O)(RE=Y 1,Eu 2)and La_(2)(IO_(3))_(6)(H_(2)O)(3)have been synthesized through facile hydrothermal methods.1 and 2 are isostructural,crystallizing in the polar space group P21,while 3 crystallizes in the polar space group Pc.1-3 feature three-dimensional(3D)frameworks composed of alternately connected corner-shared dis torted[REO_(x)]polyhedra(RE=Y,Eu,and La;x=8,9)and[IO_(3)]^(−)groups.Optical studies showed that 1–3 exhibit good NLO properties,including strong SHG intensities(3.0×(1),4.5×(2),and 1.5×KH_(2)PO_(4)(3)),large band gaps(4.12(1),4.36(2),and 4.24 eV(3),with 2 possessing the largest band gap among the known SHG-active rare-earth-based iodates,high laser damage thresholds(LDT)(53×(1),43×(2),and 44×AgGaS_(2)(3)),and wide transparency ranges(ca.3.0–11.3μm)in the mid-IR region covering two criti cal IR transparency windows;1–3 are therefore potential candidate NLO materials.Density functional theory calculations on 1–3 confirm that their strong SHG responses and large band gaps are mainly derived from the synergistic effect of[IO_(3)]^(−)groups and rare-earth oxide polyhedra[REOx]in their 3D frameworks.We conclude that the introduction of rare-earth cations with moderate electropositivity into iodates may optimize the balance between SHG effciency and optical band gaps,the key requirement for high-performance NLO materials for practical applications.
基金supported by the National Natural Science Foundation of China(21771179,21571020 and 21301175)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB20010200)the support from“Chunmiao Projects”of Haixi Institute of Chinese Academy of Sciences.
文摘The search for new non-centrosymmetric(NCS)crystals with wide energy-gaps(Eg)and strong secondharmonic generation(SHG)responses has become one of the greatest challenges in the mid-and farinfrared(MFIR)nonlinear optical(NLO)field.In this work,a novel quaternary NCS material Sr_(5)ZnGa_(6)S_(15)(SZGS),which contains a complex 3D anionic framework and possesses the optical properties required for the MFIR NLO applications,especially the good balance between wide Eg(3.15 eV)and large SHG response(d_(ij)=1.2×AgGaS_(2)),has been discovered for the first time.Moreover,the result of theoretical calculation further indicates that the 3D[ZnGa_(6)S_(15)]^(10−)framework makes definitive contributions to the NLO properties.All these studies demonstrate that SZGS is a promising NLO candidate in the MFIR region.
